The first full-length trailer for Alfonso Cuarón’s space thriller “Gravity” is out today, revealing more back story for Sandra Bullock’s astronaut heroine.

In “Gravity,” Dr. Ryan Stone (Bullock) and Matt Kowalsky (George Clooney) — the only characters whose faces appear in the film — are in their spacesuits, working on the Hubble telescope when debris from a destroyed Russian satellite collides with their space shuttle and sends Bullock’s character spinning away into the darkness.

The new trailer (watch it below) begins in silence as text appears onscreen.

“At 372 miles above the Earth there is nothing to carry sound,” it reads. “No air pressure. No oxygen. Life in space is impossible.”

What follows is much of the same footage already shown in previous teasers — Stone stranded and desperate, Kowalsky barking instructions, and a damaged shuttle hurtling out of orbit.

“You’re burning oxygen,” a voice in her helmet warns. “You have to sip, not gulp.”

The new trailer also allows a glimpse of Stone’s past.

“Is there somebody down there looking up, thinking about you?” Kowalsky asks.

“I had a daughter,” Stone whispers. “A little girl with brown hair. Tell her that I’m not quitting.”

“Gravity” actress Sandra Bullock speaks on stage during the film’s panel at San Diego’s Comic-Con International on July 20, 2013. (Jordan Strauss / Associated Press)

“I wanted her to look almost androgynous in a way, because she had experienced such loss in life,” Bullock told the Hall H audience. “I wanted her to have a body of someone who didn’t want to remind herself of what she lost.”

Filming “Gravity” was extremely physically demanding, she said, because she was required to act in a 9-by-9-foot, LED-lighted cube for the majority of filming, suspended from 12 wires, 10 feet above the ground, to simulate the weightlessness of outer space. A camera on a robot, dubbed “Iris,” filmed from all angles, sometimes moving 25 miles per hour before instantly stopping inches from her face.

It seems that her efforts won’t go unrewarded as anticipation builds for “Gravity,” and the film earns praise from the likes of James Cameron.

The “Titanic” and “Avatar” director told Variety he was “absolutely floored” by Cuarón’s film.

“I think it’s the best space photography ever done, I think it’s the best space film ever done, and it’s the movie I’ve been hungry to see for an awful long time,” he said. “Alfonso and Sandra working together to create an absolutely seamless portrayal of a woman fighting for her life in zero gravity…. She’s the one that had to take on this unbelievable challenge to perform it. [It was] probably no less demanding than a Cirque du Soleil performer, from what I can see.”